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arXiv · 2503.02848

Steady-state dynamical mean field theory based on influence functional matrix product states

Mithilesh Nayak·Julian Thoenniss·Michael Sonner·Dmitry A. Abanin·Philipp Werner
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Abstract

We implement the recently developed influence functional matrix product states approach as impurity solver in equilibrium and nonequilibrium dynamical mean field theory (DMFT) calculations of the single-band Hubbard model. The method yields numerically exact descriptions of metallic states without sharp spectral features, at a moderate numerical cost. Systems with narrow quasiparticle or spin-polaron peaks, as well as low-temperature Mott insulators provide more challenges, since these simulations require long time contours or high bond dimensions. A promising field of application is the DMFT simulation of nonequilibrium steady states, which we demonstrate with results for photo-doped Mott systems with long-lived doublon and holon populations.

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Mithilesh Nayak, Julian Thoenniss, Michael Sonner, Dmitry A. Abanin, Philipp Werner. 2025-03-04. Steady-state dynamical mean field theory based on influence functional matrix product states. https://doi.org/10.1103/xsbn-jk16

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